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Leases - Additional Information (Detail) $ in Millions | 3 Months Ended
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Mar. 31, 2019 USD ($)
Operating Lease, Weighted Average Remaining Lease Term | 5 years 8 months 12 days
Lessee, Operating Lease, Option to Extend | 5.0 years
Operating Lease Liability Not Yet Commenced | $ 0.8
Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract | 6 years 4 months 24 days
Maximum [Member] |
Operating Lease, Weighted Average Remaining Lease Term | 13 years 8 months 12 days
Minimum [Member] |
Operating Lease, Weighted Average Remaining Lease Term | 2 months 12 days

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- Definition Represents operating lease liability not yet commenced. + References No definition available. + Details
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- Definition Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980 + Details
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Balance Type: | na
Period Type: | instant

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- Definition Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980 + Details
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- Definition Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(3) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 + Details
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- Details
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- Details
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